#include <stdio.h>
#include <stdlib.h>
int main()
{
   int num;
   char var[1000];
   char out[1000];
   FILE *fptr;
   if ((fptr = fopen("D:\\input.txt","r")) == NULL){
       printf("Error! opening file");
       // Program exits if the file pointer returns NULL.
       exit(1);
   }


   int m=0;
   int flag=0;
   int k,i=0;
        while(!feof(fptr))
        {
            char ch;
            fscanf(fptr,"%c",&ch);
            var[i]=ch;
            i++;
        }
    for(k=0;k<i;k++)
    {
        if(var[k]!= ' ')
        {
            flag=0;
            out[m]=var[k];
            m++;
        }
        else if(var[k] == ' ')
        {
            if(flag == 0)
            {
                out[m]=var[k];
                m++;
                flag=1;
            }
            else
            {
                continue;
            }
        }
    }


   fptr = fopen("D:\\output.txt","w");
   if(fptr == NULL)
   {
      printf("Error!");
      exit(1);
   }

   char space = ' ';
   for(i=0;i<m-1;i++)
   {
       printf("%c ",out[i]);
       if(out[i] == 10 || out[i] == 9) //return and tab detection
       {
           out[i]=' ';
           continue;
       }

   }

 int sd=0;
 flag=0;
   for(i=0;i<m-1;i++)
   {
       if(out[i] == 32)
       {
           if(flag == 0)
           {
               flag=1;
               var[sd++]=' ';
               continue;
           }
           else
           {
               continue;
           }
       }
       else if(out[i] != 32)
       {
           var[sd]=out[i];
           sd++;
           flag=0;
       }
   }


   printf("\n\n\n\n\n\n\n\n");
   for(i=0;i<m-1;i++)
   {
        fprintf(fptr,"%c",var[i]);
        printf("%c",var[i]);
   }
   fclose(fptr);

   return 0;
}